Drill sharpener



A. E. PETERS DRILL SHARPENER Filed April l, 1930 June 30, 1931.

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INVENTOR. ZI 12% uzvELPe-Leva BY @C HIS A TTORNEX Patented June 30, 1931 unir/En Ysreres PATENT oFFicE.

, ARTHUR E. rnrnns or PHILLI-rsefnne, New JERSEY, AssIGNon To INGERsoLL-RAND @5MP-ANY, or .TERSIEY-CITY, NEW

JERSEY, A CORPORATION O'F NEW JERSEY lDRIL'I'J SHARPENER l'Applicltrlen `filed April f1, 1930. Serial :1970.44037119.

`Thisinvention relates te `drill Sharpeners, but more particularly to that type of sharpener -`in Which the Work isclai'nped or forged between 'relatively movable elements, such -as :5 anvil block and a cross head, both of which vmay be :provided with die members of suit able forin for `either clamping the Work isecurelyfin position r for forging operations, such as forming the Shanks and bits of drill 1.0l steels and similar Working implements.

`One yobject of the invention is to prevent d'estrvuctiveimpact'of the Gross head against the-anv--lfbloc'k bylsuitable cushioning devices adapted to 'become operative as the Across 1-5 headfnearsftheend of its -clampinger forging stroke. i

Other objects Wil-l 'be in part obvious and in iper-t pointed out. hereinafter.

in the accompanying drawings illustrati-ng t0 the -invention and lin Whiehsimilar reference characters Arefer to sini-iler parts,

Figurel is a. sectional elevation of a drill sharpenerconstructed inajccordance with the practieeoffftheinvention, and l 2,6, Figure-2 is a transverse view taken through Figure l on fthe line 2;-'2 vlookin-g in the direetion indicated -by the arrows.

Referring more .particularly to the drawings, A represents generally 2a drill sharpen- 50 posed a clamping cylinder C shown for the purpose-'of illustrationjas forming an -i-ntegral Vpart ej-f len -anvil block D.

The anvil block 'D is providedwithe bore E to receive slidably 1a post :or column lF to the upper end of which is secured a eross head In theopposi'njg faces of the yanvil block D 'andtheeross head G are-disposed die members which are 'designated 'according to pairs as 'H and J. These diej'members are merely shown for illustrative purposes and it is to :be understood that any dies suitable n for the Vrespective 'Work for which 'they may be intended may be vsubstituted for :those shown. Y l y The lower portion'o-fthe ybase B lmay-be yin the Aforni of a Apressure fluid vsupply reservoir K Which may communicate with a source of pressureA fluidv supply (net-shown) ithrough a 'eonneetion lL threaded vin the base B. In

er'comprising a base B upon which lis dis,

the upper region of the'bas'e B is an-end wall O which forms a head for the lower 'end of the clamping cylinder C /and depending therefrom 'is a projection or Wall-l P which may be of annular sha-pe and yhas a bore Q for the ireception of a stem R preferablVv formed integrally With ya clamping piston rec'iprocable in the-clamping cylinder C.

The clamping iston S andthe stem Rare provided with a bore T to --receive a vreduced extension U of the rod F. By formingthe reduced `extension U on the rod F a. shoulder V is provided on the rod to -form'anabutment for the upper end of the piston S.

The extension Uis of sueh length Ithat its lower end 1V projects beyond -thecorr'esponding end Aof the stem R,land Y-the projecting end W )is yprovidedvvith threads X for ythe/aecominoda'tion of a nut Y which bears tagainst-*the free end. ofthe stem R to press the clamping pistonS firmly againstthe shoulder V.

The stem R and the reducedportion U of the rod F are, in eifect,1a raising pistonysiince their lovvermost -ends are constantly exposed to the lpressure lfluid in the supply reservoir K. The arrangement is such that Ain the absence of any opposing pressures the pressure Yliu-id `acting against the `lower ends Aof the Ired F 'and the stem R, as Well as Vagainst the nut Y will lraise the cross head *G relatively -to the anvil block and Will,therefore, alsoraise theclampingpistonS. Preferably the stem R is provided with suitable sealing means sueh as a. Series of lrings Z which may be disposed in grooves fb in the stem R Vin a Well known. manner to preventleakage of pressure 4iiui'd from the supply reservoir K through the bore Q.

,The means provided for 'controlling the movement of Athe clamping ,piston S :may consist offa manually controlled vaflve c afrranged in a va-lvechestd lon the side of the Sharpener, as for instance, adjacent r.the clamping cylinder C. may `be 'disposed Within the valve Chest d 'to form a renewable wearing sur-face for y'the valve c.

The valve `c may comprise a pair of yend hea-ds f fa-ndfgconneeted by a'ste'm h, and to A :guide bushing Ve" free end ot the head f5 is connected a link manner and whereby the valve c may be manually actuated from one limiting position to the other. v

The pressure fluid controlled bythe valve c is conv-eyed to the valve chest by a passage 0 ywhich leads iromthe supply reservoir K and epens into a port p inthe valve chest al and the bushing e. The port Q7 is so located that it maybe controlled by the head fot the n valve 5 in the form of a plate and the check valve. The pressure fluid thus admitted to the valve chest ma; and through an inlet passage g leading from thevalve chest tothe upper end of the clamping ycylinder C. -Y f j ln order lto provide an escape for the pressureztluidutilized yfor actuating the clamping Y piston S down-.1y ardly, the valve chest is provided'v with a port r in thebushing c and located` below theV passage g. opens into an exhaust passage @located in the Iclamping cylinder C and in the base B and which passage s opens into an' exhaust chamber t .encircling thewall l). `ifport u in the side of the base B aiiords communication between the exhaust chamber t andv the atmosphere. s i

.dnl drill Sharpeners of the type to which the 'present' invention pertains the reciprocable parts,V such as the cross head Gnthe clamping piston'Sand-the rod' F are of necessity of rugged .construction and therefore otconsid-V ."erable weight. During their'operation it 1s s essentialf'that they reciprocate at a rapid rate ,for Jr`orgingk the working implements. It is therefore desirable that means be provided to avoid severe impact of the movable elements against the stationary elements since, other- `wise, these Aparts may become seriously damaged orbroken. The present invention contemplates the provision of means'for preventingdestructive impact of the cross head .against the anvil block or of the clamping piston S against thebase B at the end of the downward stroke'o these elements. To this end the stem R is provided with a recess 'v groove @and forming4 a part of lthe stem R i @0 Y pulsion oftheair 'from beneath the said pisform a cushioning or compression chan'iberv toV accommodate the compressed air enpreferably in the form of an annular groove through whichl the air beneath the'piston S y may escapeinto thebore Q'and thence to the exhaust vchamber t through a port or port-s fw in the wall P. y

The groove fvispreferably of such extent n -that it will be constantly in communication with the ports w. YAt'they upper end of the is a shoulderw whichis adapted to move into the borel as the pistonxS nears the end of its downward stroke toprevent the complete exton S. Preferably the lower end of the pis ton .is providedwith'acavity or recess y t0 trapped beneath the piston S after the shoulder w has cut o communication between the clamping cylinder C and the ports fw. In order to prevent the drawing ofavacuum beneath the clamping piston S as the clamp ing piston is being raised the wall O is provided with an opening a which may be threaded to receive a removable valve seat or cage 2v provided with ports 3 for admittingatmospheric 'air into the clamping cylinder C. The upper end of thecage 2 is in the form of a valve seat t to accommodate a check valve may be guided with respect to the seat l by means of a rod or bolt 6 slidable in a bore 7 in the valve cage 2. The valve plate 5 may be suitably clamped to the rod 6 by means of a nut 8, and on the lower end of the rod 6 is threaded a nut 9 which is adapted to abut the end of thevalve cage 2 for limiting the degree of lift 'of the valve plate 5.

The following is a briefdescription of the operation of the device: Let it be assumedl that the valve c occupies aposition in which communication is cut off between the passages o and g. ln this position of the valve c the upper end of the clamping cylinder C will be in communication with the atmosphere through the passage g and '8, the exhaust chamber t and the port u.y The-pressure 'fluid acting against the raising piston, such as the end of the rod F and-thenut Y,"will .then

piston S together with the crosshead G will then be actuated downwardly.

f During a portionv of the downward stroke i ofthe clamping pistonS some of the air in the lower end of the clamping cylinder C will be forced therefrom bythe piston S through the annular groove@ and the ports fw into the exhaust chamber t from whence it'will flow through the port a` tothe atmosphere. As

the vpiston S approaches the end of its downward stroke the shoulder Ywill enter the upper end of the bore'Q, thus preventing the further flow of air from the clamping cylinder C.V The air remaining in theclamping cylinder C will then be compressed and will exert a sufficient cushioning effect against the piston S to prevent actual impactofthepiston S against the wall or Vhead O; 'The.cushioning force of the air thus compressed, however, will not bel of sufficient value to materially retard the downward stroke ofthe cross head Vagainst the work. This'is-due-to-the facts'that the shoulder w isso located as to" assure only a suilicient amountof air beneath natascia the piston S to prevent contact between the said piston and the head O, and also to the volume of the'recess y which, in effect, is a cushioning chamber.

Upon reversal of the valve c the passage g will again be associated with the passage s.

The pressure fluid utilized for actuating the cross head G downwardly will then escape from the clamping cylinder C into the exhaust chamber t, thence to the atmosphere through the port a. Upon the exhausting of pressure fluid from the clamping cylinder the pressure fluid acting against the raising piston will then again raise the reciprocable parts, such as the clamping piston S and the cross head G. During this upward movement of these parts the valve plate 5 will be raised and air will flow into the cylinder C through 'the ports 3 to" assure against the drawing of a vacuum beneath the piston S and therefore the retardation of the upward movement of the cross head.

In practice the present invention has been found to be unusually eiiicient as a means for preventing breakage of the reciprocatory parts of the Sharpener. One desirable feature of the invention is that, due to the provision of the exhaust chamber t within the base B, the pressure iiuid discharged from the clamping cylinder C, as well as air expelled from beneath the piston S, may be suitably con- -trolled during its course from the clamping cylinder and may therefore be directed to the atmosphere at points where it will not cause the agitation of dust and other matter inY the vicinity of the Sharpener. This arrangement also obvia-tes the undesirable occurrence of exposing the operator to currents of exhaust fluid issuing from the Sharpener.

I claim:

1. In a drill Sharpener, the combination of an anvil block and a cross head reciprocable with respect to the anvil block, a base having a bore to form a guide, a clamping cylinder, a clamping piston in the clamping cylinder connected to the cross head having a stem reciprocating in the bore, said base having relief ports to communicate the bore with the atmosphere, there being a recess in the stem aording communication between the clamping cylinder and the relief ports, pressure actuated means for raising the cross head and the piston, and means on the stem to cooperate with the bore for cutting off the flow of the compression to .the relief ports during the clamping stroke of the piston, thereby entrapping air in the clamping cylinder to vcushion the final clamping stroke of the piston.

- 2. In a drill Sharpener, the combination of an anvilV block and a cross head reciprocable with respect to the anvil block, a base having a bore toform a guide, a clamping cylinder, a piston in the clamping cylinder connected to actuate the cross head and having a stem reciprocatinggiirrthe bore, i saidy .baseha-ving'rref lief .ports toA communicate the bore with the atmosphere, there lbeing an annular i groove inthe stem. to conveyl compression fromfthe' clamping.cylinder to the ports duringa p01'- tion of the-clampingstrcke of the piston, pressure actuatedmeans for raisingthe pis-k1 ton and the cross head, means on the stem movableinto the bore to cu-t olfthe flowy off compression tothe relief ports as ythe ypiston nears the end of its clamping stroke, thereby rentra-pping air in the clampingcylinden tofcushion the final portion oi they clamping. stroke ofthe piston, and means for admitting air into the cylinder to irevent the drawing of a vacuum therein during the return stroke of the piston.

3. In a drill Sharpener, the combination of an anvil block and a cross head reciprocable with respect to the anvil block, a base forming a raising cylinder, a clamping'cylinder, a clamping piston in the clamping. cylinder and connected to move the cross head ytoward the anvil block, a stem on the clamping pis'- ton forming a raising, piston for raising. Athe cross head, said raising cylinl der having compression relief ports therein,v4 there bein@ a recess in the stem to convey compression from the clamping cylinder to the ports during the down stroke of the clamping piston, and means on the stem to cooperate with the raising cylinder for cutting off the flow of compression from the clamping cylinder during the down stroke of the clamping piston, thereby entrapping air in the clamping cylinder to cushion the subsequent downward movement of the clamping piston.

4. In a drill Sharpener, the combination of an anvil block and a cross head reciprocable with respect to the anvil block, a base forming a raising cylinder and having an exhaust chamber therein, a clamping cylinder, a clamping piston in the clamping cylinder and connected to actuate the cross head toward the anvil block, a stem on the clamping piston reciprocable in the raising cylinder and forming a raising piston for raising the cross head, said raising cylinder having compression relief ports opening into the exhaust chamber, there being an annular groove in the stem to conveyy compression from the clamping cylinder to the ports during a port-ion of the down stroke of the pistons, and a shoulder on the stem movable into the raising cylinder for cutting olf the flow of compression from the clamping cylinder to the ports as the clamping piston approaches the end of its downward stroke, thereby entrapping compression beneath the clamping piston to cushion the piston during the remaining portion of its downward Stroke.

5. In a drill Sharpener, the combination of an anvil block and a cross head reciprocable with respect to the anvil block, a. base forming Y inder cross head towardthe anvil block, a stem on the clamping piston reciprocable inthe' port;

In testimony whereof I have signed this specification. Y

' ARTHUR E. PETERS.

ay raising ylinderiand havingan exhaustV chamber therein, a clamping cylinder, a clamping piston inthe *clamping cyland connected to aotuate raising cylinder and forming a raising piston for raising the cross head7 said raising cylinder having Compression relief ports opening into the exhaust chamber, there being 'an annular groove in the stem to convey com' vpression from the clamping cylinder to the ports during a portion of the downstroke of the pistons, ashoulder on the stemmovable into the raising cylinder for cutting off the iiow of compression from the clamping cylinder to the ports as the Clamping piston appreaches the end of yits downward stroke, thereby entrapping compression beneath the clamping piston to cushion the piston during the Aremaining portion of its downward stroke, a port in the base to admit air into the clamping cylinder beneath the clamping pistonto prevent the drawing of a vacuum during the upward stroke of the piston, and

a check valve to control the last mentioned,y

the l 

